Section 4: Narrow and One-Lane Bridges

Introduction

Narrow bridges with clear width between curbs less than 18
feet but more than 16 feet, and one lane bridges with clear width
between curbs of 16 feet or less may require advisory speeds. As
a rule, advisory speed zones should be applied for such structures
when horizontal or vertical sight distance restrictions on the approaches
require a reduction of approach speeds for safe operation. Advisory
speeds of this type are intended to eliminate the element of surprise.

Placement of Signs

The normal location of the W5-2 NARROW BRIDGE or W5-3 ONE
LANE BRIDGE signs, under which a W13-1 ADVISORY SPEED sign would
be mounted, is specified in the latest edition of the Texas
Manual on Uniform Traffic Control Devices (
TMUTCD)
(Table 2C-4). The signs may be located at a greater distance in
advance of the bridge if necessary to allow sufficient time and
distance for deceleration and may be repeated at the point where
the structure first comes into view.